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        <h3 class="title">G</h3>
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            <span class="glossterm">Guard Point</span>
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        A guard point is the last position on a function table.
        If the length is, say 1024, the table will have 1024+1 (1025) points:
        the extra point is the guard point.
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        In any case, for a 1024-point table,  the first point is index 0 and the
        last 1023; index 1024 is not really used)
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        The reason for a guard-point is that some opcodes interpolate
        to obtain a table value, in which case, when the table index is
        say, 1023.5, we need the value of the 1024 pos in order to interpolate.
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        There are two ways of filling this point (writing the value that goes
        in it):

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                Default way: by copying the value of the 1st point in the table
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            Extended Guard-Point: extending the contour of the table (continuing to
            calculate the table for one extra point)
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        In general the first mode is used for wrap-around applications, such as
        an oscillator (which loops continuously reading the table). The second
        use is for one-shot readouts, such as envelopes, where the last point
        needs to be interpolated correctly following the table contour (we are not
        looping back to the beginning of the table)
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